Can't get shared memory id Error in zmwatch.log

[cvsvs]

Hi
I have recently installed ZM (1.22) and it worked fine (with 5 cameras -- 3 color and 3 b/w) for a month.
I changed one camera to "Modect" mode and the server hung after an hour (not sure if this was a coincidence).

zmwatch.log reads:

Watchdog starting at 06/08/29 23:05:54
Watchdog pausing for 30 seconds
Can't get shared memory id '2053971978': No such file or directory

I stopped ZM service and started again; it starts fine but I can't log on and watch the Cameras.

Pls assist.

[zoneminder]

This is unlikely to be the problem. Other zm*.log or /var/log/messages may have something more useful in it. I've not heard of ZM locking up a whole server except where there are hardware problems, usually bad memory. However in that ccase the box just dies and doesn't usually just start itself back up after an hour.